The present invention relates generally to semiconductor device manufacturing and, more particularly, to methods of integrating active matrix, inorganic light emitting diodes for display devices.
Organic light emitting diode (OLED) displays have gained significant interest recently in flat panel display applications in view of their faster response times, larger viewing angles, higher contrast, lighter weight, lower power, amenability to flexible substrates, as compared to liquid crystal displays (LCDs). Despite the OLED's demonstrated superiority over the LCD, there still remain several challenging issues related to encapsulation and lifetime, yield, color efficiency, and drive electronics, all of which are receiving considerable attention.
Nonetheless, OLEDs continue to be widely investigated as a future technology choice for manufacturing flexible active matrix displays. Although passive matrix addressed OLED displays are already in the marketplace, they do not support the resolution needed in the next generation displays, since high information content (HIC) formats are only possible with the active matrix addressing scheme. Active-matrix refers to the combination of the switching and/or driving active devices (typically thin-film transistors) and the passive devices (such as LEDs) controlled by the active devices. The active and passive parts of the active matrix are typically referred to as the backplane and front plane, respectively.
In contrast to the more established inorganic LEDs, the low deposition temperature of organic materials is well compatible with low-cost flexible substrates. On the other hand, the lifetime and efficiency of currently existing organic LEDs is far below that of the inorganic LEDs.